1. Field of the Invention
The invention relates to furnaces generally and, in particular, to a portable air curtain blower for an open incineration pit.
2. Description of the Related Art
It has been a problem to eliminate or dispose of solid waste where open field or pit burning is prohibited. However, if open burning is permitted, it is also a problem to burn the waste, cheaply, cleanly, and legally on a site in a controlled manner in conformity with state and local rules and regulations.
Controlled burning at high temperatures has been found to be the best method to incinerate waste in most commercial, industrial and municipal applications. Such controlled burning is suitable for incinerating land clearing debris, including tree stumps from construction or road work, combustible demolition site waste, and seasonal collections of leaves, limbs and brush. High temperature burning also minimizes the danger of fire spreading due to wind and drought because of the controls which are in place.
However, the known devices in the prior art have not been satisfactory either from a safety standpoint or from the standpoint of meeting the strictest rules and regulations currently in effect.
For example, U.S. Pat. Nos. 3,773,000 and 4,161,916 to Applegate both disclose an apparatus for the controlled incineration of waste in an open pit. However, because of the heat generated against the earthen wall underneath the apparatus, there is a tendency for the earthen wall to collapse under the weight of the apparatus, thus causing the apparatus to roll into the pit.
Another prior art device for incinerating waste is disclosed in U.S. Pat. No. 3,927,626 to Fokakis et al. Although it is suitable for burning material in "a well defined hole in the earth", the apparatus is unfortunately not portable and it is too bulky to be converted to a portable device. In fact, in the preferred embodiment, the incineration pit is fixed and has a wall structure "of metal, fire brick, or other heat resistant material."
The prior art device disclosed in U.S. Pat. No. 3,899,984 to Keyes et al is portable and is suitable for open pit burning of waste. Also, because of the orientation of the wheels of the device, this apparatus does not have the tendency to roll into the pit. Nevertheless, since the device is made up out of a plurality of large segments connected end to end, it is difficult and time-consuming to put the apparatus together and to move it from site to site. Furthermore, if the segments are not tightly secured together by the unskilled field workers, the device operates inefficiently due to the leakage of air through the cracks left between adjoining segments.
Thus, it remains a problem in the prior art to develop an efficient and portable air blower for use adjacent to an open earthen incineration pit that meets strict environmental standards without the tendency of the blower to fall into the pit.